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1.
Scand J Med Sci Sports ; 28(4): 1451-1460, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29239030

RESUMO

The study was a two-armed, parallel group, cluster randomized controlled trial in which 15 teams (160 players) were assigned to either an experimental group (EG, 8 teams n = 86), which warmed-up with bodyweight neuromuscular exercises, or a control group (CG, 7 teams, n = 74) that performed standard tactical-technical exercises before training. All injuries during the 2015-2016 regular season were counted. Epidemiologic incidence proportion and incidence rate were also calculated. Countermovement jump (CMJ) and composite Y-Excursion Balance test (YBT) were used to assess lower limb strength and postural control. A total of 111 injuries were recorded. Chi-square test detected statistically significant differences between EG and CG (32 vs 79, P = .006). Significant differences in the injuries sustained in the EG (21 vs 11, P = .024) and CG (52 vs 27, P = .0001) during training and matches, respectively, were observed. Significant differences in post-intervention injuries were observed between in EG and CG during training (21 vs 52, P < .0001) and matches (11 vs 27, P = .006). Significant differences in epidemiologic incidence (0.37 vs 1.07, P = .023) and incidence rate (1.66 vs 4.69, P = .012) between the EG and the CG were found. Significant improvement in CMJ (+9.4%, P < .0001; d = 1.2) and composite YBT (right: +4.4%, P = .001, d = 1.0; left: +3.0%, P = .003; d = 0.8) for the EG was noted. Significant differences in post-intervention CMJ (+5.9%, P = .004) and composite YBT scores (right, +3.7%, P = .012; left, +2.3%, P = .007) between the EG and the CG were observed. Including bodyweight neuromuscular training into warm-up routines reduced the incidence of serious lower limb injuries in elite female basketball players.


Assuntos
Traumatismos em Atletas/prevenção & controle , Basquetebol/lesões , Extremidade Inferior/lesões , Condicionamento Físico Humano/métodos , Exercício de Aquecimento , Adolescente , Peso Corporal , Feminino , Humanos , Adulto Jovem
2.
Ophthalmic Epidemiol ; 8(2-3): 109-17, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11471080

RESUMO

With the Global Elimination of Trachoma by 2020 program underway, it has become increasingly important to identify the prevalence of ocular chlamydia infection in communities. DNA amplification tests are the gold standard, but are prohibitively expensive. In the present paper, we investigate whether pooling multiple specimens into a single test is feasible. The conjunctivae of 170 children in western Nepal were examined and swabbed. The prevalence of chlamydial infection was estimated in two ways using the ligase chain reaction: by testing all 170 specimens individually, and by testing 34 pools of 5 specimens each. We show that the confidence interval for 34 pooled specimens approaches that of doing all 170 specimens as the prevalence decreases. We also determine the optimal number of specimens to pool into a single test to minimize the confidence interval of the estimate. If the population prevalence is expected to be around 10%, then 14 specimens should be pooled per test. Even at 50% prevalence, costs can be reduced by pooling two samples per test.


Assuntos
Chlamydia trachomatis/isolamento & purificação , Túnica Conjuntiva/microbiologia , Manejo de Espécimes/métodos , Tracoma/epidemiologia , Criança , Pré-Escolar , Chlamydia trachomatis/genética , DNA Bacteriano/análise , Humanos , Lactente , Reação em Cadeia da Ligase/métodos , Nepal/epidemiologia , Prevalência , População Rural , Manejo de Espécimes/economia , Tracoma/diagnóstico
3.
Biochem J ; 289 ( Pt 3): 751-6, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8435072

RESUMO

Non-metabolizable analogues of glucose, including 1-O-methyl alpha-D-glucopyranoside (alpha MDG), that are co-transported with Na+ increase the specific activity of ornithine decarboxylase (ODC) in LLC-PK1 cells [Lundgren and Vacca (1990) Am. J. Physiol. 259, C647-C653]. The present study examines the effect of alpha MDG on LLC-PK1-cell ODC mRNA expression. The relative concentration of ODC mRNA in cells incubated in Earle's balanced salts solution minus glucose (EBSS--G) plus 3 mM alpha MDG was 5-6-fold higher than the concentration of ODC mRNA in cells incubated in either EBSS--G alone or in EBSS--G plus 3 mM 3-O-methyl-D-glucopyranose, a non-metabolizable analogue of glucose that is taken up by a passive carrier-mediated glucose transporter. Actinomycin D and cycloheximide completely blocked the increase in ODC activity induced by alpha MDG. Actinomycin D was also a potent inhibitor of ODC mRNA expression by alpha MDG. Cycloheximide had very little effect on the ability of this sugar to increase ODC mRNA. The relative concentration of ODC mRNA increased as a function of the incubation time in EBSS--G plus alpha MDG. The amount of ODC mRNA also increased as a function of the concentration of alpha MDG in EBSS--G. The addition of phlorizin (100 microM) to EBSS--G prevented alpha MDG from increasing ODC mRNA in LLC-PK1 cells. Phlorizin did not prevent phorbol 12-myristate 13-acetate (PMA) from enhancing LLC-PK1-cell ODC mRNA expression. The positive effect of both alpha MDG and TPA on ODC mRNA expression was suppressed when cells were incubated in hypertonic EBSS--G. From these results it is suggested that the uptake of Na(+)-dependent cotransported sugars increase ODC activity by enhancing ODC gene transcription and that this process may be dependent on cell volume expansion.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Metilglucosídeos/farmacologia , Proteínas de Transporte de Monossacarídeos/metabolismo , Ornitina Descarboxilase/genética , RNA Mensageiro/biossíntese , Animais , Transporte Biológico/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Cinética , Metilglucosídeos/metabolismo , Concentração Osmolar , Florizina/farmacologia , Sódio/metabolismo , Suínos , Acetato de Tetradecanoilforbol/farmacologia
4.
Tissue Cell ; 21(4): 479-94, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2573965

RESUMO

In adrenocortical cells, the first step in the enzymatic processing of cholesterol to steroid end products occurs in the mitochondria. ACTH increases mitochondrial cholesterol and steroidogenesis. In cultured mouse adrenocortical tumor cells, microtubule-based organelle motility may increase the proximity of mitochondria to the SER, lipid droplets and endoscome-derived lysosomes, thereby facilitating the transfer of cholesterol from these organelles to the mitochondrial outer membrane. ACTH may increase opportunities for the transfer by promoting organelle motility and by increasing the number of lysosomes. Taxol, a microtubule polymerizer, inhibits basal and ACTH-induced steroidogenesis in these cells, presumably at the step where mitochondria obtain cholesterol. We examined the ultrastructure of taxol-treated, unstimulated and ACTH-stimulated cells, seeking alterations which conceivably could interefer with the proposed organelle transport and encounters, and thus correlate with taxol's inhibition of steroidogenesis. Primary cultured cells were incubated in serum-containing medium for 4 hr with and without ACTH (10 mU/ml), with 10 micrograms/ml and 50 micrograms/ml of taxol, and with ACTH and taxol 10 or taxol 50 simultaneously. Culture media were analyzed for the presence of secreted steroids at the end of 1, 2, and 4 hr of incubation. At the end of the fourth hour, unstimulated cells and cells treated with ACTH, taxol 50, and both agents simultaneously, were fixed and processed for EM. Taxol inhibited basal and ACTH-induced steroidogenesis in a dose-dependent fashion. In both unstimulated and ACTH-stimulated cells, taxol 50 formed numerous microtubule bundles, but did not markedly change the distribution of mitochondria and lipid droplets. SER tubules, and clusters of Golgi fragments, endosomes, and lysosomes appeared to be translocated towards the cell periphery along some of the microtubules. Taxol permitted an ACTH-induced cell rounding and microfilament rearrangement considered to facilitate organelle motility. Our data indicate that taxol disrupts the formation of lysosomes by these adrenal cells, but it seemed unlikely that taxol's ultrastructural effects could prevent organelle transport proposed to cause meetings between mitochondria and the SER or lipid droplets, or prevent ACTH-caused increases in these encounters. Taxol may instead prevent the transfer of lipid droplet or SER-contained cholesterol to adjacent mitochondria, by a means not detectable in our electron micrographs.


Assuntos
Corticosteroides/biossíntese , Neoplasias do Córtex Suprarrenal/metabolismo , Alcaloides/farmacologia , Microtúbulos/metabolismo , Organelas/metabolismo , Neoplasias do Córtex Suprarrenal/ultraestrutura , Hormônio Adrenocorticotrópico/antagonistas & inibidores , Hormônio Adrenocorticotrópico/fisiologia , Animais , Masculino , Camundongos , Microtúbulos/efeitos dos fármacos , Microtúbulos/ultraestrutura , Organelas/efeitos dos fármacos , Organelas/ultraestrutura , Paclitaxel , Células Tumorais Cultivadas
5.
Tissue Cell ; 21(5): 687-98, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2575805

RESUMO

Taxol inhibits the basal and ACTH-stimulated steroidogenesis of cultured mouse adrenocortical tumor cells, presumably by preventing the arrival of cholesterol in mitochondria. In these cells, taxol polymerizes and rearranges microtubules, disperses SER masses, disrupts the Golgi, and impedes the formation of cholesterol-containing lysosomes. However, taxol's alterations in ultrastructure appear likely to permit both a microtubule-based organelle transport proposed to bring mitochondria of unstimulated cells close to alternate sources of cholesterol--the SER and lipid droplets--and postulated ACTH-caused increases in these encounters. Conceivably, taxol may prevent the transfer of cholesterol from the SER and lipid droplets to mitochondria, once the meetings are achieved. To investigate this possibility, we determined the reversibility of taxol's ultrastructural effects and inhibition of steroidogenesis. Primary cultured adrenal tumor cells were incubated for 4 hr with and without ACTH (10 mU/ml). with taxol (50 micrograms/ml), and with ACTH and taxol 50 simultaneously. Some cultures from each set were washed with fresh medium and re-incubated for 1.5 hr. with and without ACTH. Media taken from cultures at the ends of pre- and post-washout incubations were analyzed for the presence of secreted steroids. Sample cultures were fixed for electron microscopy at the ends of both incubations. Data derived from pre-washout incubations confirmed previous reports of taxol's ultrastructural changes and inhibition of steroidogenesis. When cells recovered from taxol in the absence of ACTH, the inhibition of steroidogenesis was completely reversed. In the presence of ACTH, ex-taxol-treated cells demonstrated a "rounding up' and an increased steroid production that are characteristic responses to the hormone. However, in all cases, there was a persistence of taxol's alterations in organelle numbers and arrangements. Our findings establish that the ultrastructural effects of taxol which we recorded cannot prevent mitochondria of unstimulated and ACTH-stimulated adrenal tumor cells from gaining cholesterol. They strengthened the possibility that in pre-washout incubations, taxol allowed organelle motility to bring mitochondria adjacent to cholesterol-containing SER tubules and lipid droplets, but inhibited steroidogenesis by preventing the cholesterol transfer. Taxol might limit the availability of a protein required for the transfer, an effect not visible in our electron micrographs.


Assuntos
Corticosteroides/biossíntese , Neoplasias do Córtex Suprarrenal/metabolismo , Alcaloides/farmacologia , Microtúbulos/efeitos dos fármacos , Organelas/efeitos dos fármacos , Neoplasias do Córtex Suprarrenal/ultraestrutura , Hormônio Adrenocorticotrópico/farmacologia , Animais , Transporte Biológico , Camundongos , Microscopia Eletrônica , Organelas/metabolismo , Paclitaxel , Fatores de Tempo , Células Tumorais Cultivadas
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